[NFC] Generate separate tables via macro (#137)
This is a non functional change, it allows:
- Getting rid of `unix_features_aggregator`
- Have a single blob describing the features
- Fix wrong mocking of `hwcaps`
Downside: abuse of macros makes the code slightly magical and harder to understand.
It think it's still an improvement over the current situation as there's less repetition and less chances to get something wrong.
diff --git a/src/define_tables.h b/src/define_tables.h
new file mode 100644
index 0000000..cb5ff37
--- /dev/null
+++ b/src/define_tables.h
@@ -0,0 +1,72 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// The following preprocessor constants must be defined before including this
+// file:
+// - DEFINE_TABLE_FEATURE_TYPE, the underlying type (e.g. X86Features)
+// - DEFINE_TABLE_DB_FILENAME, the db file (e.g. "cpuinfo_x86_db.inl")
+
+// This file is to be included once per `cpuinfo_XXX.c` in order to construct
+// feature getters and setters functions as well as several enum indexed tables
+// from the db file.
+// - `kGetters` a table of getters function pointers from feature enum to
+// retrieve a feature,
+// - `kSetters` a table of setters function pointers from feature enum to set a
+// feature,
+// - `kCpuInfoFlags` a table of strings from feature enum to /proc/cpuinfo
+// flags,
+// - `kHardwareCapabilities` a table of HardwareCapabilities structs indexed by
+// their feature enum.
+
+#ifndef SRC_DEFINE_TABLES_H_
+#define SRC_DEFINE_TABLES_H_
+
+#define FEATURE(ENUM, NAME, CPUINFO_FLAG, HWCAP, HWCAP2) [ENUM] = CPUINFO_FLAG,
+static const char* kCpuInfoFlags[] = {
+#include DEFINE_TABLE_DB_FILENAME
+};
+#undef FEATURE
+
+#ifndef DEFINE_TABLE_DONT_GENERATE_HWCAPS
+#define FEATURE(ENUM, NAME, CPUINFO_FLAG, HWCAP, HWCAP2) \
+ [ENUM] = (HardwareCapabilities){HWCAP, HWCAP2},
+static const HardwareCapabilities kHardwareCapabilities[] = {
+#include DEFINE_TABLE_DB_FILENAME
+};
+#undef FEATURE
+#endif // DEFINE_TABLE_DONT_GENERATE_HWCAPS
+
+#define FEATURE(ENUM, NAME, CPUINFO_FLAG, HWCAP, HWCAP2) \
+ static void set_##ENUM(DEFINE_TABLE_FEATURE_TYPE* features, bool value) { \
+ features->NAME = value; \
+ } \
+ static int get_##ENUM(const DEFINE_TABLE_FEATURE_TYPE* features) { \
+ return features->NAME; \
+ }
+#include DEFINE_TABLE_DB_FILENAME
+#undef FEATURE
+
+#define FEATURE(ENUM, NAME, CPUINFO_FLAG, HWCAP, HWCAP2) [ENUM] = set_##ENUM,
+static void (*const kSetters[])(DEFINE_TABLE_FEATURE_TYPE*, bool) = {
+#include DEFINE_TABLE_DB_FILENAME
+};
+#undef FEATURE
+
+#define FEATURE(ENUM, NAME, CPUINFO_FLAG, HWCAP, HWCAP2) [ENUM] = get_##ENUM,
+static int (*const kGetters[])(const DEFINE_TABLE_FEATURE_TYPE*) = {
+#include DEFINE_TABLE_DB_FILENAME
+};
+#undef FEATURE
+
+#endif // SRC_DEFINE_TABLES_H_